Hose couplings for liquid transfer are well known, particularly hose couplings used for the transfer of fuel into receptacles, such as vehicle tanks. Generally, the hose coupling is received by an adapter on the receptacle to permit the transfer of liquid, such as a fuel, into the receptacle. It is common for such hose couplings and adapters to possess normally closed internal valves to prevent the escape of fuel when the hose coupling and adapter are not engaged but which are adapted to open in response to the mating or engagement of coupling with adapter. It is also common for the coupling and adapter to engage in a locked manner to prevent separation while the internal valves of both are open during fuel transfer.
An example of a hose coupling and adapter system including the features set out above is the liquid transfer apparatus described in U.S. Pat. No. 3,674,061 to E.R. Wiggins, Inc. In this instance, the hose coupling or nozzle and receptacle adapter are locked by an arrangement of locking pins in the nozzle which engage an annular groove in the adapter and are prevented from movement therefrom by a retaining collar. When fueling is complete and release of the hose coupling from the receptacle adapter is desired, a flexible wire handle is manually manipulated by the operator to release the nozzle from its locked position within the adapter.
U.S. Pat. No. 3,662,793, also issued to E.R. Wiggins, Inc., describes another liquid transfer apparatus comprising a hose coupling adapted to mate with a receptacle adapter, the engagement of which is also releasable by manipulating a flexible wire handle. On mating, the hose coupling and adapter are locked in a manner analogous to that described above. An arrangement of pivoted dog latches in the coupling, as opposed to locking pins, engage an annular groove in the adapter and are retained in the locked position by a retaining collar until manually released by manipulation of the wire handle.
A disadvantage of such prior systems lies in the fact that release of the hose coupling from the receptacle is a two-handed operation in which one hand is required to hold the coupling while the other hand is required to disable the locking mechanism engaging the coupling and adapter. This can be problematic in many circumstances. For example, in instances where access to the receptacle is restricted, one-handed operation of the hose coupling would clearly be advantageous. One-handed operation of the hose coupling would provide the operator with greater maneuverability to access the receptacle, hold open an access door or balance himself or herself, as needed. Moreover, the arrangement of the coupling handle and lock release mechanism commonly favours right-handed operation, making left-handed operation difficult, if possible at all.
There is a need, thus, for an improved hose coupling which can be disengaged from its mating adapter on a receptacle using only one hand, and which can be used ambidextrously.